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91.
Herd R. P., Ko L., Weisbrode S. E. and Heath D. D. 1984. Sequential morphologic changes in adult Echinococcus granulosus during complement-mediated lysis in vitro. International Journal for Parasltology14:141–149. Sequential changes (5,10, 20, 30,40, 50 min, 1, 2, 3, 4, 5, 6, 7, 8, h) were observed by light, scanning and transmission electron microscopy after 38-day-old adult Echinococcus granulosus were exposed to 50% guinea pig serum in vitro. Early changes within 3 h included contraction of worms, fusion of microtriehes, vacuolization and vesiculization of the distal cytoplasm, followed by rupture of vesicles leading to erosion and loss of the distal cytoplasm. This was most marked in the terminal proglottid but ultimately there was complete erosion of the distal cytoplasm of all proglottids and the scolex. After 3 h there was loss of definition of organelles, apparent edema of the perinuclear cytoplasm and, in some instances, rupture of the circular muscle layer with extrusion of parenchyma. Adult tape-worms exposed to heat-inactivated complement showed none of these changes. Lysis and death of the parasite was attributed to osmotic changes subsequent to the formation of trans-membrane channels induced by complement-mediated attack of the tegument after activation of the alternate pathway by factors present in the cestode tegument.  相似文献   
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This review focuses on utilization of plant lectins as medical diagnostic reagents and tools. The lectin-related diagnostic is aimed at detection of several diseases connected to alteration of the glycosylation profiles of cells and at identification of microbial and viral agents in clinical microbiology. Certain lectins, proposed for or used as diagnostic tools could even recognize those cellular determinants, which are not detected by available antibodies. Broad information is presented on the lectinomics field, illustrating that lectin diagnostics might become practical alternative to antibody-based diagnostic products. In addition, the rising trend of lectin utilization in biomedical diagnostics might initiate a development of innovative methods based on better analytical technologies. Lectin microarray, a rapid and simple methodology, can be viewed as an example for such initiative. This technology could provide simple and efficient screening tools for analysis of glycosylation patterns in biological samples (cellular extracts, tissues and the whole cells), allowing thus personalized detection of changes associated with carbohydrate-related diseases.  相似文献   
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Rhesus monkeys have been kept in horizontal position under klinostatic or antiorthostatic hypokinetic conditions for 7 and 19 days. Using scanning electron microscope, studies were made of the otolithic membrane of the utricle, the receptor surface of the utricle, crista ampullaris of the lateral semicircular canals, the organ of Corti, the stria vascularis and spiral ligament. No significant differences were found between control and experimental animals.  相似文献   
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Sleep and Biological Rhythms - Neurovascular coupling (NVC), the transient regional hyperemia following the evoked neuronal responses, is the basis of blood oxygenation level-dependent techniques...  相似文献   
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The bicarbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions. However, its use in dissolution testing of solid oral dosage forms is very limited. The reason for this is the thermodynamic instability of the solution containing hydrogen carbonate ions and carbonic acid. The spontaneous loss of carbon dioxide (CO2) from the solution results in an uncontrolled increase of the pH. In order to maintain the pH on the desired level, either a CO2 loss must be completely avoided or the escaped CO2 has to be replaced by quantitative substitution, i.e. feeding the solution with the respective amount of gas, which re-acidifies the buffer after dissociation. The present work aimed at the development of a device enabling an automatic pH monitoring and regulation of hydrogen carbonate buffers during dissolution tests.  相似文献   
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